The importance of ornithological observations with respect to Columbus' discovery of America as recorded in the "Diario del descubrimiento" is recognized. The fact that his first and crucial crossing of the Atlantic coincided with the autumn migration may have contributed to its success. Columbus' log contains the first historical record of the [Magnificent] Frigate Bird, Fregata magnificens Mathews, 1914, in the Cape Verdes, with a surprisingly accurate description of its characteristic habits.